202 PROCEEDINGS OF THE AMERICAN ACADEMY 



* * * Flores majusculi ochroleuci ? Stipulaj vix vaginantes. 



30. A. Oreganus, Nutt. 1. c. Nanus, hirsutulo-canescens ; foliolis 

 obovatis eniarginatis ; floi'ibus in pedunculo brevi spicato-capitato ; 

 caljce cylindraceo tubo dentibus bis longiori ; ovario fere senii-bilocel- 

 lato. — Western slope of the Rocky Mountains, collected only by Nut- 

 tall, without fruit. Arranged among ochroleucous species in the Flora 

 of North America ; but the color of the corolla is not recorded, nor can 

 it be determined from the only specimen I have seen, that in herb. Tor- 

 rey. The stipules, at least the lower ones, are connate almost to the top. 



§ 13. MicroloU. Legumen minimum (lin. 2 - 3 longum), estipitatum, 

 coriaceum seu cartilagineum, 6 - 7-ovulatum, elliptico-ovatum, aut 

 fere tei'es postice vix complanatum, aut postice late concavum, sem- 

 per uniloculare, sutui-a neutra introflexa, ventrali costiformi crassa 

 extus prominente. — Subcinei-ei : caules erecti vel adscendentes e 

 radice perenni, graciles, rigiduli ; foliolis 5 - 8-jugis linearibus. 

 Stipula3 inferiores subconnata?, ca^terie discretas. Racemi spici- 

 formes, multiflori, virgati. Flores parvi, purpurei, per anthesin 

 recurvo-patentes ; calyce brevi, dentibus abbreviatis. 



Here are two closely allied species which have been confounded, and 

 indeed are not readily distinguished without the fruit ; one of which, by 

 the strong concavity of the dorsal face of the legume, would be looked 

 for in Astragalus pi'oper, while the other, wanting this concavity, is 

 referable to Phaca, where it would be sought among the Scytocarpi. 



31. A. GRACILIS, Nutt. in Fras. Cat., & Gen. 2, p. 100. A. parvi- 

 foUus, Nutt. in herb. Acad. Philad. Dalea parvijiora, Pursh, Fl. 2, 

 p. 474. Caulibus virgatis (ultrapedalibus e radice prailonga dulci) ; 

 foliolis angustissime linearibus fere filiformibus obtusis retusisve (hn. 

 7-10 longis) ; racemis longe pedunculatis elongatis densifloris ; tiori- 

 bus pallide purpureis albidisve (lin. 3 longis) ; leguminibus paten- 

 tibus coriaceis dorso impresso quasi cymbiformibus canescenti-pilosis 

 demum glabellis transversim rugoso-venosis, sutura ventrali suba- 

 cuta. — Plains of Nebraska and Missouri to the Rocky Mountains. — 

 This and the following species may have been confounded from the 

 first. Except as to the fruit, Nuttall's original description would as 

 well or better apply to A. microlohus ; but the original specimens 

 preserved are of the plant here retained as A. gracilis. From his 

 tickets it appears that he more recently noticed that there were two 

 species ; but the fruit of the second species, which confirms the distinc- 



